Radiation therapeutic head, collimator assembly, and control method of radiotherapeutic equipment

ABSTRACT

A radiation therapeutic head, a collimator assembly, and a control method of a radiotherapeutic equipment are provided. The therapeutic head includes: a source carrier; first radiation sources for focusing therapy and a second radiation source for conformal therapy that are disposed on the source carrier; a switch body located on an emitting side of the first and second radiation sources and provided with through holes therein, the switch body being configured to control alignment of the through holes with the first and second radiation sources to allow the emission of rays from the first and second radiation sources; and a collimator assembly, the collimator assembly further includes a carrier; a focusing collimator and a multi-leaf collimator disposed on the source carrier.

CROSS REFERENCE

The present application is a continuation application of U.S. patentapplication Ser. No. U.S. Ser. No. 15/358,140, publication No. US20170246480, titled RADIOTHERAPY APPARATUS INCORPORATING MULTI-SOURCEFOCUSING THERAPY AND CONFORMAL AND INTENSITY-MODULATED THERAPY, filed onNov. 22, 2016, which is a national phase application of the PCTapplication of PCT/CN2014/078091, publication No. WO2015176265, titledMULTI-SOURCE FOCUSING TREATMENT AND CONFORMAL INTENSITY MODULATEDRADIOTHERAPY EQUIPMENT AND COLLIMATOR COMBINATION THEREOF, filed on May22, 2014. Each of the foregoing patent applications is herebyincorporated by reference in its entirety.

TECHNICAL FIELD

The disclosure relates to the technical field of large medicalequipment, and more particularly to a radiation therapeutic head formulti-source focusing therapy and conformal intensity-modulated therapy,a collimator assembly, and a control method of a radiotherapeuticequipment.

BACKGROUND

Radiation therapy is a common treatment for treating a tumor.Stereotaxic gamma-ray systemic therapy system (hereinafter referred toas Gamma Knife) is a radiotherapeutic equipment, and there are generallytwo kinds of radiotherapy approach in the process of gamma-ray therapy,one for stereotactic focused radiation therapy with multi-source andanother for intensity-modulated radiation therapy. The stereotacticmulti-source focused radiation therapy approach refers to emit gammaradiation beams across the body of a patient and focus to one focalpoint through the body, for destroying the tumor. However, when theshape of the tumor is complicated, a conformal radiotherapy would beneeded. The so-called conformal intensity-modulation therapy refers toemploy a multi-leaf collimator, to make a shape of a radiation fieldplane for treatment similar to the shape of the tumor.

SUMMARY

An aspect of the present disclosure provides a radiation therapeutichead for multi-source focusing therapy and conformal intensity-modulatedtherapy. The therapeutic head includes: a source carrier; firstradiation sources for focusing therapy and a second radiation source forconformal therapy that are disposed on the source carrier; a switch bodylocated on an emitting side of the first and second radiation sourcesand provided with through holes therein, the switch body beingconfigured to control alignment of the through holes with the first andsecond radiation sources to allow the emission of rays from the firstand second radiation sources; and a collimator assembly, the collimatorassembly further includes a carrier; a focusing collimator and amulti-leaf collimator disposed on the source carrier.

Another aspect of the present disclosure provides a collimator assembly.The collimator assembly includes a carrier; a focusing collimator and amulti-leaf collimator disposed on the carrier.

Yet another aspect of the present disclosure provides a control methodof a radiotherapeutic equipment. The control method includes acquiring apatient's therapy plan. The radiotherapeutic equipment comprises atherapeutic head, and the therapeutic head further comprises firstradiation sources for focusing therapy and a second radiation source forconformal therapy. The therapy plan includes: performing radiotherapywith multi-source focusing or conformal intensity modulation, orperforming radiotherapy with both multi-source focusing and conformalintensity modulation successively. The method also including controllingthe therapeutic head according to the therapy plan to carry outtreatment of the patient.

The present disclosure provides a radiotherapy apparatus incorporatingmulti-source focusing therapy and conformal intensity-modulated therapy,to achieve a purpose of implementing both accurate multi-source focusedtherapy and conformal therapy in a single Gamma Knife device.

One embodiment of the present disclosure provides a radiotherapyapparatus incorporating multi-source focusing therapy and conformalintensity-modulated therapy, comprising a base, a movable couch, agantry, at least one therapeutic head, and a counterweight, the movablecouch and the gantry are disposed on the base, the therapeutic head andthe counterweight are oppositely positioned on the gantry. Thetherapeutic head comprises: a shielding part, configured for shieldingradiation beams from at least one radiation source; a source carrierreceived in the shielding part, provided with first focusing radiationsources for focused therapy and a second conformal radiation source forconformal intensity-modulated radiotherapy; a switch body positioned onan emitting side of the first focusing radiation sources and the secondconformal radiation source, and comprises at least one through hole tobe controlled aligning with the focusing radiation sources or theconformal radiation source for passing through the radiation beams; ashielding door positioned on one side of the switch body away from thesource carrier, configured for controllably shielding the radiationbeams of the radiation sources; and a collimator assembly, comprising acollimator carrier, and a plurality of focusing collimators and amulti-leaf collimator disposed on the collimator carrier.

Preferably, at least two rows of focusing radiation sources are arrangedon opposite sides of the source carrier, and a conformal radiationsource is disposed in the middle of the source carrier.

Preferably, each row comprises 9 focusing radiation sources for focusedtherapy and is equidistantly distributed in an arc sector with a centralangle arranged between 26° to 60°, along an radial axial cross sectionof the gantry.

Preferably, the two rows of focusing radiation sources are distributedon two sides of the conformal radioactive source with an included anglearranged between 26° to 60°, along an axial radial cross section of thegantry.

Preferably, the through hole comprises two rows of first through holesprovided on two lateral lines of the switch body and corresponding tothe focusing radiation sources for focused therapy, and a second throughhole arranged in the middle of the switch body corresponding to theconformal radiation source for conformal therapy, and the second throughhole is offset from a symmetry line of the two rows of first throughholes.

Preferably, the shielding door comprises two layers which arerespectively movable in perpendicular directions to mutually be openedor closed.

Preferably, the focusing collimator is mounted on the collimator carrierand capable of moving together with the collimator carrier, andcomprises three groups of collimating holes corresponding to the sourcecarrier for directing the focusing radiation from the focusing radiationsources, each group of collimating holes comprises two rows ofcollimating holes with same aperture diameter, and the distance betweentwo rows of collimating holes in each group is substantially equal, andthe apertures size of the collimating holes in different group aredifferent.

Preferably, the focusing collimator is provided with a square hole inthe middle of two rows of collimating holes of each group, and themulti-leaf collimator is received in the square hole.

The present invention further provides a collimator assembly comprising:a collimator carrier, and a plurality of focusing collimators and atleast one multi-leaf collimator disposed on the collimator carrier. Thefocusing collimator is provided with a square hole and groups ofcollimating holes configured for directing the radiation emitted bycorresponding radiation sources, each group of collimating holescomprises two rows of collimating holes in same aperture diameter, andthe apertures size of the collimating holes in different group aredifferent, two rows of collimating holes in each group are located ontwo sides of the square hole with substantially same distance.

Preferably, the focusing collimators comprise three groups ofcollimating holes.

By using the radiotherapy apparatus incorporating multi-source focusingtherapy and conformal intensity-modulated therapy disclosed in thepresent invention, both accurate multi-source focused therapy andconformal therapy can be implemented in one radiotherapy apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a radiotherapy apparatus incorporatingmulti-source focusing therapy and conformal intensity modulationtherapy, according to an embodiment of the present disclosure;

FIG. 2 is a schematic cross-sectional view of a therapeutic head of theradiotherapy apparatus of FIG. 1;

FIG. 3A is a schematic view from a top surface of a source carrier ofthe therapeutic head of FIG. 2;

FIG. 3B is a cross-sectional schematic view along line 3B-3B of thesource carrier of FIG. 3A;

FIG. 3C is a cross-sectional schematic view along line 3C-3C of thesource carrier of the therapeutic head of FIG. 2;

FIGS. 4A to 4C are the views of the position relation between the sourcecarrier, switch body, shielding door, collimator carrier and collimatorof the therapeutic head of FIG. 2, during two kinds of therapeuticsources being closed at the same time, and during the conformal sourceand the focused source being opened; and

FIG. 5 is a schematic view of the collimator carrier of the therapeutichead of FIG. 2 with a focusing collimator and multi-leaf collimatordisposed thereon.

DETAILED DESCRIPTION

For making the purpose, the technical proposal and advantages ofembodiments of the disclosure more clear, the technical proposal of theembodiments of this disclosure may be described clearly and fully usingthe figures included. Clearly, the described embodiments are only partsof the embodiments of this disclosure and not all of the embodiments.Based on the embodiments of this disclosure, all other embodimentsobtained without contributing any creative effect by those skilled inthe art are within the scope of protection of this disclosure.

In order to better understand the technical solution of the presentinvention, the Applicant has explained the radiation therapy system ofthe embodiment of the present invention by way of the specificembodiment of FIG. 1. FIG. 1 is a schematic view of a radiotherapyapparatus incorporating multi-source focusing therapy and conformalintensity modulation therapy, according to an embodiment of the presentinvention. As shown in FIG. 1, the radiotherapy apparatus includes abase, a gantry, a therapeutic head, a counterweight, and a movablecouch. The base supports the whole radiotherapy apparatus, and plays arole of carrying the whole radiotherapy apparatus and a role offixation. The gantry is arranged on the base, and is connected to thebase by a rolling support. The gantry rotates around an axial line bymeans of, e.g. gear driving, to achieve purpose of rotational treatment.The therapeutic head is the core component of the whole device, and isconnected with the gantry. The therapeutic head is driven by the gantryto rotate around the gantry axis to perform rotational treatment. Thetherapeutic head may perform focused irradiation by focusing theradiation of cobalt source, or may perform conformal irradiation bypassing radiation of a conformal cobalt source through a multi-leafcollimator. The counterweight is mounted on the gantry relative to thetherapeutic head, for balancing the weight of the therapeutic head, sothat the gravity center of the gantry coincides with its rotationcenter, to ensure the stability of the gantry in the process ofrotation. The treatment couch is arranged on the base, and is movablyconnected to the base, e.g. by screws and/or pins. The treatment couchis used to support and position a patient, and can accurately deliverthe patient to a specified position for treatment.

In combination of FIGS. 2 to 3B, the therapeutic head which is the corecomponent of the overall device, comprises a shielding part, a sourcecarrier, a switch body, a shielding door, a collimator carrier, afocusing collimator, a multi-leaf collimator, and associated driving ormotivation support members which are not shown FIG. 2. The driving ormotivation support members (hereinafter referred to as driving members)are conventional technology skilled in the art and will not be describedin this embodiment as long as it can realize the functions mentionedbelow.

The shielding part is configured to isolate the radioactive sources fromthe external environment, to shield the radiation of the radiationsources. The source carrier is located in the shielding part, and tworows of radiation sources in total of 18 (for each row of 9) arearranged on the opposite sides of the source carrier for focusingtherapy. The middle of the source carrier is also provided with aradiation source for conformal therapy (hereafter referred to asconformal source), as shown in FIG. 3A. The conformal source is centeredin the source carrier and the two rows of focusing sources have anincluded angle of 26° to 60° in the axial cross section (i.e., the planeparallel to the Z-Y plane in FIG. 2), preferably, the focusing sourcesare distributed on both sides with included angle of 48°, as shown inFIG. 3B. The source carrier are equidistantly distributed in anarc-shaped area from angle 26° to 60° in a radial cross section (i.e., aplane parallel to the Z-X plane in F FIG. 2, and X in F FIG. 2 is notshown, but it should be known that X is perpendicular to the Y-Z plane),as shown in FIG. 3C.

In combination of FIG. 2 and FIGS. 4A to 4B, the switch body is locatedon the side of the source carrier facing away from the shielding part,that is, under the source body, and the radiation emitted from the tworadiation sources is emitted from the same side. The switch body canmove along the radial direction (i.e., in the Y-direction in FIG. 2)with respect to the source carrier driven by the driving members. Twosides of the switch body are provided with two rows of firstthrough-holes A corresponding to the radiation sources for focusingtherapy and a second through-hole B corresponding to the radiationsource for conformal therapy, and the second through-hole B is offsetfrom the symmetrical line (not shown) of the two rows of firstthrough-holes A. As such, the switch body is driven to three differentpositions corresponding to situations of simultaneously closing the twokinds of sources (FIG. 4A), opening the conformal source (FIG. 4B) andopening the focusing source (FIG. 4C).

In combination of FIG. 2, the shielding door is located on the side ofthe switch body facing away from the source carrier, configured for thepurpose of controllably shielding the radiation of the radiationsources. The shielding door includes two layers respectively capable ofbeing opened in radial direction and axial direction (i.e. thedirections parallel to the direction of X and Y coordinates), thus theradiation can be completely shielded while the device is not on work.FIG. 2 only shows a second shielding door in a closed situation which isaway from the switch body. Since the arrangement and the movementdirection of a first shielding door closer to the switch body areperpendicular to that of the second shielding door, the state of thefirst shielding door is not shown in the schematic drawing, but theperson skilled in the art will understand that the movement of the firstshielding door coincides with that of the second shielding door.

Please refer to FIG. 2 and FIG. 5, the collimator carrier can be mountedinside the shielding door or outside the shielding door, and can rotateand move within the gantry. The collimator carrier is used for receivingthe focusing collimators and the multi-leaf collimator so that the twokinds of collimators can be driven as required by the driving of thedriving member. Thus, the collimator carrier, the focusing collimatorand the multi-leaf collimator constitute a collimator combination. Thisarrangement can make the collimator and multi-leaf collimator placed onthe same layer, saving a lot of space, so as to effectively increase theradial treatment space.

The focusing collimator is mounted on the collimator carrier and can bemoved and rotated together therewith. The focusing collimator isprovided with a square hole in the middle thereof. And three groups ofcollimating holes corresponding to the radiation sources are arrangedalong two sides of the square hole, configured for collimating thefocusing radiation. Each group of collimating holes includes two rows ofcollimating holes with same aperture diameter, and the aperture of thecollimating holes in different groups is different. The distance betweenthe two rows of collimating holes in each group is approximately equal.By choosing different collimating holes with different aperture,different sized focal points can be chosen, so that the focus is moreaccurate. Of course, the focusing collimator is not limited to threegroups of collimating holes.

The multi-leaf collimator is mounted at the square hole of the focusingcollimator. Different opening size with different shape is formed basedon the movement of each blade of the multi-leaf collimator, to achieve aperfect match between the shape of the radiation sources and the shapeof the tumor at the distance for therapy, to further achieve theconformal irradiation. The multi-leaf collimator would be prior art andwill not be described again in this embodiment.

In the treatment of patients, at first, image acquisition for thepatient is performed, and a treatment plan for the patient's lesions ismade by a treatment planning software. At this time, the doctor willdetermine to choose which one of the focused head and the conformal headfor treatment based on the shape, location, size of the tumor, or chooseboth of them to treat the lesion with one after another. After the planis determined, it is sent to the control computer, and ready fortreatment.

When the patient lies on the movable couch, the patient could bepositioned thereon by means of a reset device and a fixation device.After the patient is positioned, a control machine for treatment readsthe treatment plan of the patient to select one of the focusedradiotherapy or the conformal radiotherapy. When the plan specifiesemploying the focused radiotherapy, the switch body is moved to anopening position of the focusing source, the two-layer shielding doorare opened, the collimator carrier is moved to select the appropriatecollimating hole according to the plan, to carry on the tumor treatment.When the plan specifies employing conformal therapy, the switch body ismoved to an open position of the conformal source, the two-layershielding door are opened, the multi-leaf collimator is also opened, andthe radiation field corresponding to the plan is formed according to theplanned position, to carry out tumor conformal treatment.

In the embodiment of the present invention, when the tumor of thepatient is treated, a conformal irradiation, a focused irradiation, or acombination of the conformal irradiation and the focused irradiation canbe selected according to the shape and size of the tumor, adapted totreat tumor in different shapes, to achieve a more perfect therapeuticeffect.

It is to be understood that the foregoing is intended only as a specificembodiment of the disclosure and is not intended to limit the scope ofthe disclosure. The scope of protection of the present disclosure is tobe understood to be within the scope of the present disclosure asdefined by the equivalents thereof or equivalents thereof or to anyother related art, either directly or indirectly, by the use of thepresent specification and drawings.

What is claim is:
 1. A radiation therapeutic head for multi-sourcefocusing therapy and conformal intensity-modulated therapy, thetherapeutic head comprising: a source carrier; first radiation sourcesfocusing therapy and a second radiation source for conformal therapythat are disposed on the source carrier; a switch body located on anemitting side of the first and second radiation sources and providedwith through holes therein, the switch body being configured to controlalignment of the through holes with the first and second radiationsources to allow the emission of rays from the first and secondradiation sources; and a collimator assembly, the collimator assemblyfurther comprising: a carrier; and a focusing collimator and amulti-leaf collimator disposed on the carrier.
 2. The therapeutic headaccording to claim 1, wherein the first radiation sources for focusingtherapy are disposed on two opposite sides of the source carrier, andthe second radiation source for conformal therapy is disposed in amiddle of the source carrier.
 3. The therapeutic head according to claim1, wherein the therapeutic head is configured to be rotatable about anaxis, and the first radiation sources for focusing therapy aredistributed in a sector region with an angle range of 26° to 60° on aradial cross section of the axis.
 4. The therapeutic head according toclaim 1, wherein the therapeutic head is configured to be rotatableabout an axis, and the first radiation sources for focusing therapy aredistributed on both sides of the second radiation source for conformaltherapy at angles of 26° to 60° on an axial cross section of the axis 5.The therapeutic head according to claim 1, wherein the through holescomprise first through holes corresponding to the first radiationsources for focusing therapy, and a second through hole corresponding tothe second radiation source for conformal therapy, and the secondthrough hole is configured to be deviated from a symmetry line of thefirst through holes.
 6. The therapeutic head according to claim 1,wherein the collimator assembly is provided with: multiple groups ofcollimating channels for collimating focusing rays emitted by the firstradiation sources for focusing therapy; and a hole for mounting themulti-leaf collimator.
 7. The therapeutic head according to claim 1,wherein the therapeutic head further comprises a shielding body locatedoutside the source carrier for shielding the radiation rays of the firstand second radiation sources.
 8. The therapeutic head according to claim1, wherein the therapeutic head further comprises a shielding doorlocated on a side of the first and second radiation sources facing awayfrom the source carrier for controllably shielding the rays of the firstand second radiation sources.
 9. The therapeutic head according to claim8, wherein the shielding door has two layers, and the shielding door isconfigured to be opened or closed in directions perpendicular to eachother.
 10. The therapeutic head according to claim 1, wherein thetherapeutic head further comprises a switch body driving member, theswitch body is movable in a radial direction relative to the sourcecarrier under the driving of the switch body driving member, and/or thecollimator assembly driving member is configured to drive the focusingcollimator and the multi-leaf collimator to move.
 11. A collimatorassembly, comprising: a carrier; and a focusing collimator and amulti-leaf collimator disposed on the carrier.
 12. The collimatorassembly according to claim 11, wherein the collimator assembly isprovided with: multiple groups of collimating channels for collimatingfocusing rays emitted by first radiation sources for focusing therapy;and a hole for mounting the multi-leaf collimator.
 13. The collimatorassembly according to claim 11, wherein the collimator assembly isadapted to be attached to a therapeutic head that is rotatable about anaxis, and the first radiation sources for focusing therapy aredistributed in a sector region with an angle range of 26° to 60° on aradial cross section of the axis.
 14. The collimator assembly accordingto claim 11, wherein two rows of the first radiation sources forfocusing therapy are disposed on two opposite sides of the sourcecarrier.
 15. The collimator assembly according to claim 11, wherein thecollimator assembly is adapted to be attached to a therapeutic head thatis rotatable about an axis, and the radiation sources for focusingtherapy are distributed on both sides of the radiation source forconformal therapy at angles of 26° to 60° on an axial cross section ofthe axis.
 16. A control method of a radiotherapeutic equipmentcomprising: acquiring a patient's therapy plan, the radiotherapeuticequipment comprising a therapeutic head, and the therapeutic headfurther comprises first radiation sources for focusing therapy and asecond radiation source for conformal therapy, and the therapy plancomprising: performing radiotherapy with multi-source focusing orconformal intensity modulation, or performing radiotherapy with bothmulti-source focusing and conformal intensity modulation successively;and controlling the therapeutic head according to the therapy plan tocarry out treatment of the patient.
 17. The control method according toclaim 16, further comprising: when the therapy plan is to performradiotherapy with multi-source focusing, the radiotherapeutic equipmentperforms the following operations: moving a switch body of theradiotherapeutic equipment to a focusing source opening position;opening a shielding door of the radiotherapy equipment; and moving acollimator of the radiotherapeutic equipment to select appropriatecollimating holes for focusing radiotherapy.
 18. The control methodaccording to claim 16, comprising: when the therapy plan is to performradiotherapy with conformal intensity modulation, the radiotherapeuticequipment performs the following operations: moving a switch body of theradiotherapeutic equipment to a conformable source opening position;opening a shielding door of the radiotherapeutic equipment; and drivinga multi-leaf collimator of the radiotherapeutic equipment, and forming acorresponding radiation field according to the plan to perform conformaltherapy of tumors.
 19. The control method according to claim 16,comprising: when the therapy plan is to perform radiotherapy with bothmulti-source focusing and conformal intensity modulation successively,the radiotherapeutic equipment performs the following operations: movinga switch body of the radiotherapeutic equipment to a focusing sourceopening position; opening a shielding door of the radiotherapeuticequipment; moving a collimator of the radiotherapeutic equipment toselect appropriate collimating holes for focusing radiotherapy; movingthe switch body to a conformable source opening position; opening theshielding door; and controlling a multi-leaf collimator, and forming acorresponding radiation field according to the therapy plan to performconformal therapy of tumors.
 20. The control method according to claim16, comprising: when the therapy plan is to perform radiotherapy withboth multi-source focusing and conformal intensity modulationsuccessively, the radiotherapeutic equipment performs the followingoperations: moving a switch body of the radiotherapeutic equipment to aconformable source opening position; opening a shielding door of theradiotherapeutic equipment; controlling a multi-leaf collimator of theradiotherapeutic equipment, and forming a corresponding radiation fieldaccording to the therapy plan to perform conformal therapy of tumors;moving the switch body to a focusing source opening position; openingthe shielding door; and moving a collimator to select appropriatecollimating holes for focusing radiotherapy.